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688
FXUS63 KUNR 181050
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
450 AM MDT Sat May 18 2024

.KEY MESSAGES...

- Dry, cooler and breezy today.

- Warmer Sunday with thunderstorms. Strong to severe storms
  possible Sunday afternoon and evening.

- Unsettled pattern continues through the coming week.

&&

.DISCUSSION...(Today Through Friday)
Issued at 202 AM MDT Sat May 18 2024

Current surface map places cold front across eastern South Dakota
into central Nebraska. Best pressure rises are currently over
western South Dakota with a few gusts around 50 mph just east of
the Black Hills. Winds will continue to drop off through the night
as pressure rise bubble moves east. Tail end of shortwave is
bringing a few showers to far northwestern South Dakota with this
activity shifting north and east of the forecast area in the next
few hours. Surface high builds across the are today, with
cooler/breezy conditions.

Upper trough moves across the northern Rockies Sunday with surface
low tracking through eastern Wyoming into the Black Hills area
during the day. Low level thermal ridge peaks Sunday afternoon,
with highs in the 70s to lower 80s. Thunderstorms chances
increase during the day with steep mid level lapse rates and an
uptick in low level moisture. MLCAPE around 1000J/KG and
sufficient bulk shear will support a severe threat from the Black
Hills into central South Dakota.

Upper trough lingers across the Pacific Northwest/Northern
Rockies through much of the coming week with a series of impulses
crossing the area. This will result in daily chances for showers
and thunderstorms and temperatures near seasonal averages.

&&

.AVIATION...
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(For the 12Z TAFS Through 12Z Sunday Morning)
Issued At 450 AM MDT Sat May 18 2024

VFR conditions are expected through the TAF period. Breezy
northwest winds will continue across the western South Dakota
plains today then decrease in the late afternoon.
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&&

.UNR WATCHES/WARNINGS/ADVISORIES...
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SD...None.
WY...None.
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&&

$$

DISCUSSION/KEY MESSAGES...7
AVIATION...13